End mill

An end mill is a type of milling cutter, a cutting tool used in industrial milling applications. It is distinguished from the drill bit in its application, geometry, and manufacture. While a drill bit can only cut in the axial direction, a milling bit can generally cut in all directions, though some cannot cut axially.

End mills are used in milling applications such as profile milling, tracer milling, face milling, and plunging.

Types

Several broad categories of end- and face-milling tools exist, such as center-cutting versus non-center-cutting (whether the mill can take plunging cuts); and categorization by number of flutes; by helix angle; by material; and by coating material. Each category may be further divided by specific application and special geometry.

It is becoming increasingly common for traditional solid end mills to be replaced by more cost-effective inserted cutting tools (which, though more expensive initially, reduce tool-change times and allow for the easy replacement of worn or broken cutting edges rather than the entire tool).

Numeral prefix

Numeral or number prefixes are prefixes derived from numerals or occasionally other numbers. In English and other European languages, they are used to coin numerous series of words, such as unicycle – bicycle – tricycle, dyad – triad – decade, biped – quadruped, September – October – November – December, decimal – hexadecimal, sexagenarian – octogenarian, centipede – millipede, etc. There are two principal systems, taken from Latin and Greek, each with several subsystems; in addition, Sanskrit occupies a marginal position. There is also an international set of metric prefixes, which are used in the metric system, and which for the most part are either distorted from the forms below or not based on actual number words.

Table of number prefixes in English

In the following prefixes, a final vowel is normally dropped before a root that begins with a vowel, with the exceptions of bi-, which is bis- before a vowel, and of the other monosyllables, du-, di-, dvi-, tri-, which are invariable.

Mill (currency)

The mill or mille (₥) (sometimes mil in the UK, when discussing property taxes in the United States, or previously in Cyprus and Malta) is a now-abstract unit of currency used sometimes in accounting. In the United States, it is a notional unit equivalent to ¹⁄₁₀₀₀ of a United States dollar (a tenth of a cent). In the United Kingdom it was proposed during the decades of discussion on the decimalization of the pound as a ¹⁄₁₀₀₀ division of the pound sterling. Several other currencies used the mill, such as the Maltese lira.

The term comes from the Latin "millesimum", meaning "thousandth part".

Usage

United States

In the United States, the term was first used by the Continental Congress in 1786, being described as the "lowest money of account, of which 1000 shall be equal to the federal dollar."

The Coinage Act (1792) describes milles and other subdivisions of the dollar:

The mint of Philadelphia made half cents worth 5 mills each from 1793 to 1857.

Tokens in this denomination were issued by some states and local governments (and by some private interests) for such uses as payment of sales tax. These were of inexpensive material such as tin, aluminium, plastic or paper. Rising inflation depreciated the value of these tokens in relation to the value of their constituent materials; this depreciation led to their eventual abandonment. Virtually none were made after the 1960s.

Mill (heraldry)

Mill are sometimes used as a charge in heraldry, usually as a sign for agricultural or industrial endevours.

Examples

A watermill in the arms of Viana de Jadraque, Spain

A watermill in the arms of Viana de Jadraque, Spain

A windmill in the arms of a Van Garrett family

A windmill in the arms of a Van Garrett family

See also

End

End or Ending may refer to:

End

END

Ending

See also

Conclusion (music)

In music, the conclusion is the ending of a composition and may take the form of a coda or outro.

Pieces using sonata form typically use the recapitulation to conclude a piece, providing closure through the repetition of thematic material from the exposition in the tonic key. In all musical forms other techniques include "altogether unexpected digressions just as a work is drawing to its close, followed by a return...to a consequently more emphatic confirmation of the structural relations implied in the body of the work."

For example:

End (graph theory)

In the mathematics of infinite graphs, an end of a graph represents, intuitively, a direction in which the graph extends to infinity. Ends may be formalized mathematically as equivalence classes of infinite paths, as havens describing strategies for pursuit-evasion games on the graph, or (in the case of locally finite graphs) as topological ends of topological spaces associated with the graph.

Ends of graphs may be used (via Cayley graphs) to define ends of finitely generated groups. Finitely generated infinite groups have one, two, or infinitely many ends, and the Stallings theorem about ends of groups provides a decomposition for groups with more than one end.

Definition and characterization

Ends of graphs were defined by Rudolf Halin (1964) in terms of equivalence classes of infinite paths. A ray in an infinite graph is a semi-infinite simple path; that is, it is an infinite sequence of vertices v₀, v₁, v₂, ... in which each vertex appears at most once in the sequence and each two consecutive vertices in the sequence are the two endpoints of an edge in the graph. According to Halin's definition, two rays r₀ and r₁ are equivalent if there is another ray r₂ (not necessarily different from either of the first two rays) that contains infinitely many of the vertices in each of r₀ and r₁. This is an equivalence relation: each ray is equivalent to itself, the definition is symmetric with regard to the ordering of the two rays, and it can be shown to be transitive. Therefore, it partitions the set of all rays into equivalence classes, and Halin defined an end as one of these equivalence classes.